1. Field of the Invention
The present invention relates to containers and an particular to containers for sterile preparations for example for medical use.
2. Related Art
A well-known method of manufacturing containers for sterile preparations is the blow-fill-seal method in which a container is blow moulded from thermoplastics, filled with the desired preparation, which cools the thermoplastics, and then sealed. This is a convenient and inexpensive method of manufacturing such containers which has the particular advantage that the entire process may be carried out in a sterile or aseptic environment such that sterility of the container contents can be guaranteed.
A container manufactured by this method is described in EP-A-0 088 056. According to this document, the neck of the container is formed with a sealing upper section and a lower section, the two sections being connected by a frangible connection When the upper section is removed, by rupturing the frangible connection, the lower section is left in the form of a female Luer cone and may be connected to a standard male Luer connector, as commonly used in medical applications.
However, the blow moulding process used to form the container disclosed in EP-A-0 088 056 suffers from the major disadvantage that the thickness of the moulded thermoplastic cannot be consistently guaranteed. Thus, the Luer cone formed on the container cannot be guaranteed to be accurately formed, and this is an essential requirement for a Luer connection, as such a connection must form an entirely reliable seal.
WO 91/08729 discloses a similar container wherein the lower section of the neck forms a Luer lock connector. This container suffers from similar disadvantages to that of EP-A-0 088 056.
In an attempt to provide accurate connectors as part of a standard blow-fill-seal container, there have been suggested a number of containers including an insert, separately moulded from the container proper and inserted in the container before it is sealed. One such insert is disclosed in EP-A-0 685 400. An insert has the advantage that it may be moulded separately from, and therefore more accurately than, the rest of the container.
However, such inserts are generally undesirable as they complicate the manufacture of the blow-fill-seal container and in addition an insert located inside the sealed container with sterile contents must itself be sterile and this can be difficult to achieve with complete reliability.
EP-A-0 510 854 discloses a blow-fill-seal container and a cap which fits over the neck of the container. The cap has an internal needle which pierces the container as, or immediately before, the cap is placed over the container neck. The needle has a central duct which terminates externally in a receptor suitable for connection to a syringe.
U.S. Pat,. No. 5,427,275 discloses a blow-fill-seal container with a cap. The cap has an internal conical piercer which pierces the closure of the container when the cap is screwed onto the container neck. The piercer has channels formed therein which allow communication of the contents of the container with a section of the cap in the form of an external dropper, after piercing